Sharp-shinned
Hawk and Western Bluebird
Thomas Quinn
1993
Watercolor
Private Collection
While Red-tailed
Hawks only occasionally take bird prey,
Sharp-shinned Hawks only occasionally do not.
Sharp-shin take down prey either by stealth,
targeting an individual from a concealed perch,
or by speed, darting to overtake an inferior
flyer. Like lions who keep the herd strong by
culling the weak, pigeon-sized sharpies help
serve to keep a balance among prey.
It is likely
that loss of nest cavities poses a greater
threat to Western Bluebirds numbers than do
losses to avian predators, and loss of woodland
habitat poses a greater threat to Sharp-shinned
Hawks than do declines in any particular
passerine species.
Encouraging the
bluebird to remain at Stanford involves
continued availability of nest boxes such as
those dotting the Dish and encouraging the
sharpy involves preservation of woodland habitat
replete with bare perching (feather-plucking)
sites.
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